This is how Pic share works, We might need to add a video here.
Now you are going to be forwarded to Google pages which will ask you to grant the permissions to Showzey to access your email messages.

Showzey uses the industry standard protocol called OAuth which enables you give access Showzey to Gmail mails without sharing your password.

Note that Showzey will access only email messages which match the following criteria:

messages which have links to Flickr, Picasa, Kodak, or other photo sharing services.
message which have photo attachments
For messages which match the above criteria only the following parts will be persisted in our database:

subject of the message
sender's email address
date of the message
message id
links to photo sharing sites (only links no text)
photo attachments
The other parts of email messages are not persisted in any way, shape or form.
Please be assured that Showzey takes the privacy and security very seriously.